comctl32: Scroll listview when performing a marquee selection

[Owen Rudge]

Hi Nikolay,

> I don't think you need such duplication. Why not to use a single 
> rectangle? Looks like you always offset it to listview origin,
> so these rectangle differ in offset only, that's why you introduced 
> another iterator_* helper. If I'm right about that it's better to
> add another OffsetRect than consistently maintain two variables with 
> same meaning.

On second thoughts, having looked at this a bit, I think that if I 
weren't to have the two separate rectangles, I would still need to 
record the previous offset.

In the MarqueeHighlight function, the old draw rectangle is invalidated 
(which has been offsetted by the previous call), and then the old 
absolute rectangle is used for the inversion of the selected items. Then 
the new rectangle is created, and is adjusted by the present offset.

If we wanted to store only one rectangle, the previous offset - which 
would differ from the present offset - would also need to be stored, in 
order to cancel out the marquee draw and the item selection, which use 
different figures.

So it's either two rectangles being stored, or one rectangle with the 
previous offset. So I may as well leave it as it is, I think.

It might of course just be that I've been staring at this bit of code 
too long and have missed something obvious!

I'll submit a new patch anyway that adds in a check in WM_KILLFOCUS to 
stop a marquee selection if focus is lost.

Cheers,

Owen